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Bleeding risk and reproductive capacity among patients with factor XIII deficiency: a case presentation and review of the literature.

Factor XIII deficiency is an uncommon, inherited bleeding disorder that usually manifests in infancy or early childhood, involving both boys and girls. We present the case of a woman who had experienced two previous intracranial bleeding events, and was treated before and during her current pregnancy with factor XIII concentrate. Her pregnancy was successful, and she experienced an uncomplicated vaginal delivery. To better understand the issues surrounding bleeding, reproductive capacity, and management of factor XIII deficiency during pregnancy, we conducted a systematic literature review using MEDLINE from 1966 to December 1998. We also examined the bibliographic references from all articles, and included all cases, case reports, or case series of patients with factor XIII deficiency. We retrieved data on 117 patients from 37 articles, the majority of which had type II deficiency. Among untreated patients with type II factor XIII deficiency, the literature suggests an elevated mortality rate due to uncontrolled bleeding and intracranial hemorrhage. Because of its high degree of efficacy, the evidence supports the use of life long prophylactic therapy with at least monthly infusions of factor XIII concentrate, including during pregnancy. The opinion that women with type II factor XIII deficiency have inevitable recurrent abortions, or that men are sterile, is not well substantiated. No data were found on whether treatment alters male reproductive capacity. A policy of universal factor XIII replacement, starting in childhood, will likely enable more patients to attain reproductive status. The development of an international data registry would optimally address both bleeding risk and reproductive capacity among patients with factor XIII deficiency.

Adult↗

Role of coagulation testing in predicting bleeding risk.

Coagulation testing is employed widely prior to open surgery and invasive procedures. This is based on the assumption that such testing is of clinical value in the prediction of bleeding. In order to improve the clinical understanding of the potential limitations of first-line coagulation tests used in this way, we have systematically reviewed the literature that addresses the value of routine coagulation testing in helping to predict bleeding risk. We conclude unreservedly that indiscriminate coagulation testing is not useful in a surgical or a medical setting. This is due to the limited sensitivity and specificity of the tests, coupled with the low prevalence of bleeding disorders resulting in a high number of false positives, poor positive predictive value for bleeding and numerous false negatives resulting in false reassurance. Since most abnormal results can be predicted and most cases of significant bleeding disorder identified from a complete clinical assessment, the employment of selective laboratory testing is more cost-effective and represents evidence-based clinical practice.

Adult↗

[Control of the heparin induced bleeding risk in haemodialysis patients (author's transl)].

Partial-Thromboplastin-Time (PTT) has been used as a bedside-method to control the dosage of heparin in haemodialysis patients at a high bleeding risk. The practical procedures and the advantages of the method as compared to current coagulation controls are outlined. As a result a technique of "minimal intermittent heparinization" has been developed which effectively prevents bleeding in the heparinized patient on haemodialysis.

Blood Coagulation Disorders↗

Assessment of a bleeding risk index in two cohorts of patients treated with oral anticoagulants.

In two cohorts of patients on oral anticoagulant therapy, routinely treated by the Leiden Thrombosis Service, the frequency of major bleeding complications was assessed during two years (1988 and 1991). With Poisson regression analysis the influence of the risk factors age, sex, target zone, achieved INR and type of coumarin derivative used were determined. Subsequently, a bleeding risk index was calculated, combining the results of the two cohorts. For various types of patients the relative risk of major bleeding complications was assessed. Age and achieved INR were the most important and consistent risk factors: rate ratio (RR) for age in 1988 1.46 per 10 years increase (95% confidence interval [CI] 1.20-1.78) and in 1991 1.57 per 10 years increase (95% CI 1.23-2.00); RR per unit increase in achieved INR in 1988 1.42 (95% CI 1.21-1.68) and in 1991 1.44 per unit increase in achieved INR (95% CI 1.18-1.74). Two methods were used to combine the results of 1988 and 1991. In the first method the mean bleeding risk index was calculated: In (incidence) [natural logarithm of the incidence rate of major bleeding] = -5.64+ 0.42 * age +0.26 * sex -0.29 * target range +0.36 * achieved INR -0.36 * coumarin type. In the second method only the consistent risk factors age and achieved INR were used: In (incidence) = -5.64 -0.42 * age +0.36 * achieved INR. These bleeding risk indexes can be used to assess the risk of major bleeding complications of individual patients and allow more individualized care by individual tailoring the desired anticoagulation.

Administration, Oral↗

A prospective, randomized trial of endoscopic hemoclip placement and distilled water injection for treatment of high-risk bleeding ulcers.

BACKGROUND: Although endoscopic hemoclip therapy is widely used in the treatment of GI bleeding, there are few prospective trials that assess its efficacy. This study evaluated the efficacy and safety of hemoclip placement and distilled water injection for the treatment of high-risk bleeding ulcers. METHODS: Seventy-nine patients with major stigmata of ulcer hemorrhage were randomly assigned to either endoscopic hemoclip placement (n = 39) or injection with distilled water (n = 40). RESULTS: Initial hemostasis was achieved in all patients treated with hemoclips and 39 treated by distilled water injection (respectively, 100.0% vs. 97.5%; p = 1.00). Bleeding recurred in 4 and 11 of patients, respectively, in the hemoclip and water injection groups. It occurred significantly more frequently in the injection group (hemoclip, 10.3%; injection, 28.2%; p = 0.04). No major procedure-related complication occurred in either group. Emergency operations were performed in 5.1% of patients treated with hemoclips versus 12.5% of those in the water injection group (p = 0.43). Hospital days and mortality rate were similar in both groups. CONCLUSION: Endoscopic hemoclip placement is a safe and effective hemostatic method that is superior to distilled water injection for treatment of bleeding peptic ulcer.

Female↗

Bleeding risk of combined oral anticoagulant and antiplatelet therapy in cardiovascular disease.

BACKGROUND: In controlled clinical trials with patients with cardiovascular disease, both antiplatelet and oral anticoagulant therapy have proved effective in reducing thrombotic and thromboembolic complications. The combination of both therapeutic strategies has been evaluated in several cardiovascular conditions. METHODS: A meta-analysis was performed on the bleeding risk in six published trials of combined oral anticoagulant and antiplatelet therapy. RESULTS: The results of clinical trials (in patients with artificial heart valves and in patients with unstable angina or non-Q myocardial infarction) suggest that combined oral anticoagulant and antiplatelet therapy may be as safe as oral anticoagulation alone. Also, in a large study of healthy subjects the safety of combined oral anticoagulant and low-dose antiplatelet therapy was acceptable at one to two major bleedings per 100 person-years more than with oral anticoagulation alone. CONCLUSIONS: The safety of combined oral anticoagulant and antiplatelet therapy is probably acceptable, provided the antiplatelet therapy is given in a low dose. These results warrant an efficacy and safety evaluation of combined oral anticoagulant and low-dose antiplatelet therapy in large clinical trials.

Administration, Oral↗

Antegrade access in a stented common femoral artery: feasible but with a real bleeding risk.

Antegrade femoral artery access is often used for diagnostic and interventional purposes in patients with critical limb ischemia, given its potential advantages in terms of visualization and back-up. However, it may be associated with an increased risk of local vascular complications, especially in the presence of common femoral artery atherosclerosis. We hereby report a case of antegrade femoral access in a previously stented common artery, which enabled successful recanalization of a totally occluded superficial femoral artery. Despite the procedural success, retroperitoneal bleeding occurred after sheath removal, which was nonetheless effectively managed with prolonged balloon inflations by means of contralateral femoral artery access. This clinical vignette, the first to date to report on antegrade access in a stented femoral artery, supports its feasibility despite the presence of a real bleeding risk.

Aged↗

Clinical application of procedural platelet monitoring during percutaneous coronary intervention among patients at increased bleeding risk.

The goal of platelet function testing in the catheterization laboratory is to provide information about the platelet contributions to the risk of thrombotic or hemorrhagic events and optimization of anti-platelet therapy for percutaneous interventions. We present several illustrative cases in which platelet monitoring with the Rapid Platelet Function Assay (RPFA, Accumetrics) was used to guide dosing of a glycoprotein (GP) IIb/IIIa inhibitor for coronary and peripheral intervention among patients at increased bleeding risk.

Abciximab↗

Bovine thrombin-induced inhibitor of factor V and bleeding risk in postoperative neurosurgical patients. Report of three cases.

Three patients are reported who developed topical bovine thrombin-induced antibodies to clotting factor V following neurosurgical procedures. In each patient the coagulopathy occurred within 8 to 13 days following exposure to topical bovine thrombin at surgery. Two of the three had previously been exposed to bovine thrombin during cardiothoracic surgery. The three patients were identified by detection of a prolonged prothrombin time, ranging from 20.5 to 39.8 seconds. The patient with the highest factor V level (0.12 U/ml) experienced gastrointestinal bleeding, which ceased when the factor V level increased to more than 0.20 U/ml. One patient required a ventriculostomy. In that case the prothrombin time and factor V level failed to improve following administration of vitamin K, 10 units of fresh frozen plasma, and platelet transfusions; the factor V level temporarily increased from 0.03 to 0.32 U/ml following a 2-day course of intravenous gamma globulin (1 gm/kg/day). Plasmapheresis has also been reported to be transient benefit in the treatment of this coagulopathy. In most patients the factor V level rises and the prothrombin time improves toward normal within 3 to 6 weeks following surgical exposure. The individuals identified likely represent only a fraction of the patients who develop the coagulopathy. The latter either do not bleed or are not sufficiently challenged in the postoperative period for the bleeding risk to be tested. It is concluded that bovine thrombin-induced coagulopathy may occur following surgical exposure to topical bovine thrombin and may result in both postoperative morbidity and mortality in a subset of patients.

Aged↗

Anti-thrombotic effects and bleeding risk of AJvW-2, a monoclonal antibody against human von Willebrand factor.

1. A murine anti-human vWF monoclonal antibody, AJvW-2, was developed that inhibited the interaction between platelet glycoprotein Ib (GPIb) and von Willebrand factor (vWF) during the ristocetin- (IC50 = 0.7 +/- 0.1 microgram ml-1) and botrocetin- (IC50 = 1.8 +/- 0.3 microgram ml-1) induced aggregation of human platelets. 2. AJvW-2 inhibited the high shear stress (10.8 N m-2) induced aggregation of human platelets dose-dependently with an IC50 = 2.4 +/- 0.3 micrograms ml-1, but had no effect on low shear stress induced platelet aggregation (1.2 N m-2) up to 100 micrograms ml-1. 3. AJvW-2 also inhibited the high shear stress (5.0 N m-2) induced adhesion of human platelets to collagen I with the same efficacy (IC50 = 2.4 +/- 0.3 micrograms ml-1), but no effect at low shear conditions (1.5 N m-2). 4. AJvW-2 inhibited the botrocetin-induced aggregation of platelets from guinea-pig, rat, rabbit, dog and pig at the same concentration range as human platelets; it likewise also inhibited the high shear stress induced aggregation and adhesion to collagen I of guinea-pig platelets. 5. AJvW-2 prevented arterial thrombus formation in guinea-pigs at a dose of 100 micrograms kg-1 without prolonging the template bleeding time, whereas the GPIIb/IIIa antagonists lamifiban mediated inhibition of thrombosis at 1000 micrograms kg-1 was accompanied by a significant prolongation of the bleeding time. 6. These results suggest that AJvW-2 is a potent inhibitor of the GPIb-vWF interaction and a potential novel antithrombotic agent with lower bleeding risk than GPIIb/IIIa antagonists.

Animals↗

Cerebral arteriovenous malformations: influence of angioarchitecture on bleeding risk.

BACKGROUND: To evaluate the angioarchitecture of cerebral arteriovenous malformations (cAVMs) with special regard to its influence on the risk of intracranial haemorrhage. METHODS: Clinical and neuroradiological data of 171 patients with cAVMs, who were treated at our department, were analysed retrospectively. The angioarchitectonic data were obtained from angiographic series, cranial CT scans and MR images. A chi(2) test was conducted to correlate the parameters and determine the P values. FINDINGS: The following parameters correlate to an increased risk of haemorrhage: diameter of the nidus < or =2 cm (P<0.001), number of arterial feeders < or =2 (P<0.001), diameter of the main feeder < or =1 mm (P<0.0001), number of veins draining the nidus < or =2 (P<0.001), exclusive deep drainage (P<0.05), and low or middle flow-velocity (P<0.01). Specific angioarchitectonic features such as venous stenoses, varicose dilatation of the draining vein, arterial aneurysms of the feeding artery, arteriovenous fistula within the nidus, contralateral drainage and sinushypo/-aplasia did not alter the bleeding rate. INTERPRETATION: Various angiographic features were correlated with the occurrence of intracranial haemorrhage in patients with cerebral AVMs. In addition to the well-known factors influencing the bleeding risk of cAVMs like size, pattern of venous drainage and location within the brain our data demonstrate the importance to look at the diameter of the main feeder and the number of draining veins showing a better correlation.

Adolescent↗

Bleeding risk factors in chronic oral anticoagulation with acenocoumarol.

We studied major bleeding complications, death related to hemorrhage, and tried to identify predisposing factors for bleeding in outpatients treated with acenocoumarol. We evaluated 811 outpatients attending a specialized anticoagulant therapy unit. The intended INR range was 3.5-4.5 for mechanical heart valve replacement (N= 384) and 2.0-3.0 for other indications (N= 427). The variability of INR for the total follow-up and the 2 months before the hemorrhage was calculated. The total follow-up was 1,963.26 years with 27,321 control tests. We observed 47 major bleeding episodes, including 2 fatal (central nervous system hemorrhages), in 37 patients. 49.5% of the patients had underlying diseases. The rate of major and fatal hemorrhage was 2.39 and 0.10 episodes per 100 patients year, respectively. Hemorrhagic complications were more frequently observed in patients with a more intense intended range (8.2% in the INR 3.5-4.5 group vs. 1.5% in the 2.0-3.0 INR group). The risk of major bleeding increased in patients with an achieved INR higher than 6 and in those with higher INR variability during follow-up. The estimated probability of bleeding also increased with time: it was 0.102% at 78 months, and at the beginning of therapy it was 0.006% and 0.007% at 1 and 4 months, respectively. The intensity of anticoagulation and the deviation of the INR from the target are the most important risk factors for bleeding in patients taking acenocoumarol. Monitoring the variability of INR can help identifying patients predisposed to bleeding. However, the screening for underlying disease should always be performed.

Acenocoumarol↗

Combination therapy with aspirin, clopidogrel and warfarin following coronary stenting is associated with a significant risk of bleeding.

Dual antiplatelet therapy of aspirin and a thienopyridine is the standard of care following coronary stenting. Patients who are on chronic warfarin therapy and receive a coronary stent need to be treated with the triple therapy of aspirin, clopidogrel and warfarin; however, the bleeding risk in these patients is unknown. To evaluate the bleeding risk in patients requiring chronic warfarin therapy and undergoing stent implantation, we compared 107 consecutive patients on chronic warfarin therapy who underwent coronary stenting and were discharged on aspirin, clopidogrel and warfarin to 107 contemporary patients who were treated with aspirin and clopidogrel. We evaluated their bleeding history before and after coronary stenting. Major bleeding was defined as bleeding that was significantly disabling, intraocular or requiring at least 2 units of blood transfusion. Minor bleeding was defined as other bleeding that led to interruption of the medications. Patients on triple therapy were younger and more likely to have hypertension. This group had significantly higher major bleeding (6.6% vs. 0%; p = 0.03) and minor bleeding (14.9% vs. 3.8%; p = 0.01) compared with the dual antiplatelet therapy group. In the triple therapy group, the international normalized ratio or aspirin dosage did not influence the bleeding risk. In patients requiring warfarin therapy, the addition of dual antiplatelet therapy is associated with an approximately 7% major bleeding risk. Thus, novel regimens are needed to reduce the bleeding risk.

Aged↗

Treatment of porcine sepsis with high-dose antithrombin III reduces tissue edema and effusion but does not increase risk for bleeding.

We evaluated the effectiveness of antithrombin III (AT III) infusions designed to achieve supraphysiologic plasma levels of this serine protease inhibitor in preventing vascular permeability and disseminated intravascular coagulation in a pig model of sepsis. In addition, we determined whether high AT III doses were associated with increased bleeding risk. Sepsis was induced in 18 pigs by injection of lipopolysaccharide (LPS) (0.25 microg/kg per h for 3 h). At 90 min after the start of LPS infusion, pigs were randomized (n = 6 per group) to receive either human serum albumin as a placebo, AT III 120/5 (120 U/kg, 30-min bolus + 5 U/kg per h for 240 min), or AT III 250/10 (250 U/kg + 10 U/kg per h). Three additional animals served as negative controls (no LPS, no AT III). Treatment with AT III significantly reduced the amount of effluents in body cavities and fibrin monomers. AT III did not significantly increase bleeding risk as determined by organ hemorrhage. An additional assessment of AT III's bleeding risk [skin bleeding time (SBT)] was carried out in 35 nonseptic pigs treated with either AT III alone (120/5 or 250/10) or in the combination with heparin. Heparin administration alone produced a dose-dependent increase in SBT, but AT III alone did not. Addition of AT III 120/5 to heparin did not induce a further increase in bleeding time over heparin alone. These results indicate that administration of AT III in doses designed to achieve very high plasma concentrations significantly ameliorates symptoms of sepsis-induced vascular leakage and disseminated intravascular coagulation without increasing bleeding risk.

Animals↗

Factors affecting bleeding risk during anticoagulant therapy in patients with atrial fibrillation: observations from the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study.

BACKGROUND: Stroke and systemic thromboembolism are serious problems for patients with atrial fibrillation (AF), but their incidence can be substantially reduced by appropriate anticoagulation. Bleeding is the major complication of anticoagulant treatment, and the relative risks for bleeding vs stroke must be considered when starting anticoagulation. METHODS: The AFFIRM trial included patients with AF and at least one risk factor for stroke, randomly assigning them to either a rate-control or rhythm-control strategy. All patients were initially treated with warfarin. The incidence of protocol-defined major and minor bleeding was documented during follow-up. Variables associated with bleeding were determined using a Cox proportional hazards model, using baseline and time-dependent covariates. RESULTS: The 4060 patients in the AFFIRM trial were followed for an average of 3.5 years. Major bleeding occurred in 260 patients, an annual incidence of approximately 2% per year, with no significant difference between the rate-control and rhythm-control groups. Increased age, heart failure, hepatic or renal disease, diabetes, first AF episode, warfarin use, and aspirin use were significantly associated with major bleeding. Minor bleeding was common in both treatment arms, with 738 patients reporting this problem in one or more visits. CONCLUSIONS: Bleeding is a significant problem that complicates management of patients with AF. Risk factors for bleeding can be identified, and knowledge of these risk factors can be used to plan therapy.

Aged↗

Predictors of bleeding risk and long-term mortality in patients with acute coronary syndromes.

OBJECTIVE: The aim of this review was to collate the published evidence on independent predictors of bleeding and late mortality in acute coronary syndrome (ACS) patients, to compare the two sets of risk factors, and to investigate whether bleeding is reported as a predictor of late mortality. RESEARCH DESIGN AND METHODS: Computerized searches, covering the period from 1999 to July 2004, were performed on MEDLINE, EMBASE, and the Cochrane Library database. Studies were eligible for inclusion in the review if they related to patients with ACS and included an assessment of risk factors for bleeding, mortality, or both. Studies that did not meet these criteria were excluded. MAIN OUTCOME MEASURES: A total of 937 studies were retrieved, of which 912 were excluded from the review because they did not meet the defined criteria. RESULTS: The available evidence suggests that any impact of bleeding on mortality is confined to the short term. In studies that showed a significant association between bleeding and risk of mortality, association between bleeding and risk of mortality, this was always related to in-hospital or 30-day mortality. By contrast, studies of long-term mortality consistently showed that bleeding was not an independent predictor. Furthermore, follow-up studies showed that adverse outcomes in hospital and within the first month were not related to 1-year mortality. This may reflect the beneficial impact of anticoagulant therapy on subsequent cardiovascular risk in patients with ACS, which outweighs any shortterm detrimental effect of bleeding. CONCLUSIONS: The available evidence suggests that any impact of bleeding on mortality in ACS patients appears to be confined to the short term, and long-term outcomes do not reflect the impact of in-hospital bleeding.

Angina, Unstable↗

Prediction of the risk of bleeding during anticoagulant treatment for venous thromboembolism.

OBJECTIVES: To construct and validate the bleeding risk prediction score, which is based on variables identified in the literature that can be easily obtained before the institution of anticoagulant therapy, in a large independent cohort of patients who were treated with anticoagulant therapy for established venous thromboembolism to allow for quantitative assessment of the risks and benefits of the therapy and to adapt the patient's management accordingly. METHODS: We constructed a bleeding risk prediction score, based on variables and their odds ratios identified in the literature, which can be easily obtained before the institution of anticoagulant therapy (score = [ 1.6 X age] + [1.3 x sex] + [2.2 X malignancy]). Subsequently, we evaluated the score in a test group of 241 patients treated with anticoagulant therapy for venous thromboembolism to determine the optimal cutoff points for the prediction of hemorrhagic complications, using receiver operating characteristic curve analysis. We then validated this score in an independent cohort of 780 patients. A score of 3 or more points, 1 to 3 points, or 0 points represented a high, intermediate, or low bleeding risk, respectively. RESULTS: The score in about one fifth of the patients in the test group was classified as predicting high risk for bleeding complications. The risk of all bleeding complications was 26% in this group and the risk of major bleeding complications was 14%. The area under the curve was 0.75 (95% confidence interval, 0.64-0.84) and 0.82 (95% confidence interval, 0.66-0.98) for all bleeding complications and major bleeding complications, respectively. When validated, there was a moderate loss of predictive power of the score, but the categorization of the patients by the score remained clinically useful; 20% of the patients were classified as high risk, and the bleeding rate was 17% for all bleeding complications and 7% for major bleeding complications compared with 4% and 1%, respectively, in those categorized as low risk. CONCLUSIONS: With the use of 3 easily obtainable, clinical variables in a prediction model, it is possible to identify a subgroup of patients at the start of anticoagulant therapy who have a high risk of developing hemorrhagic complications. Further studies should address whether additional measures to prevent bleeding decrease the bleeding incidence without compromising efficacy.

Anticoagulants↗

Injection of fibrin tissue adhesive versus laser photocoagulation in the treatment of high-risk bleeding peptic ulcers: a controlled randomized study.

BACKGROUND AND STUDY AIMS: A controlled and randomized multicenter study was carried out in order to compare the efficacy of fibrin sealant and Nd:YAG laser photocoagulation in patients with high-risk arterial bleeding from peptic ulcers of the stomach and the small intestine. PATIENTS AND METHODS: In four teaching hospitals, 53 patients presenting with either active arterial ulcer bleeding (Forrest class 1 a) or a large visible vessel in the ulcer base (diameter over 2 mm, Forrest class 2 a) were treated with infiltration of epinephrine 1: 10,000 followed by the injection of fibrin tissue adhesive (n = 28), or with epinephrine plus laser photocoagulation (n = 25). Permanent hemostasis for at least seven days served as the principal end point; rebleeding, emergency surgery, and hospital mortality served as further end points. RESULTS: There were no significant differences between the study groups in terms of age, risk factors, initial hemoglobin values, number of patients showing signs of hemodynamic impairment, ulcer size and localization, or bleeding activity. Primary hemostasis was achieved in all patients. Rebleeding rates were seven of 28 and four of 25 among the patients treated with fibrin sealant and laser coagulation, respectively (not significant). There were no significant differences regarding the rates of ultimate hemostasis (24 of 28 vs. 24 of 25), emergency surgery (four of 28 vs. one of 25), or hospital mortality (0 vs. two of 25). No complications occurred with either form of treatment. Patients who had a visible vessel in the ulcer floor at the first control endoscopy had a significantly higher incidence of rebleeding, regardless of the type of endoscopic therapy. CONCLUSIONS: We conclude that both the injection of fibrin tissue adhesive and laser photocoagulation are effective methods of treating high-risk arterial peptic ulcer bleeding. As the number of high-risk patients necessary to reach significance are difficult to recruit within a reasonable period even in a multicenter study, a new meta-analysis of all studies now available should be considered.

Epinephrine↗